================================================================== BUG: KCSAN: data-race in ext4_ext_insert_extent / ext4_mark_iloc_dirty read-write to 0xffff888137c11ac2 of 2 bytes by task 26 on cpu 0: le16_add_cpu include/linux/byteorder/generic.h:146 [inline] ext4_ext_insert_extent+0x1981/0x2b50 fs/ext4/extents.c:2113 ext4_ext_map_blocks+0x16a3/0x1fc0 fs/ext4/extents.c:4259 ext4_map_blocks+0x700/0xfc0 fs/ext4/inode.c:628 mpage_map_one_extent+0x10d/0x390 fs/ext4/inode.c:2387 mpage_map_and_submit_extent fs/ext4/inode.c:2440 [inline] ext4_writepages+0xa41/0x1e30 fs/ext4/inode.c:2792 do_writepages+0x7b/0x150 mm/page-writeback.c:2352 __writeback_single_inode+0x84/0x560 fs/fs-writeback.c:1461 writeback_sb_inodes+0x6a0/0x1020 fs/fs-writeback.c:1721 __writeback_inodes_wb+0xb0/0x2a0 fs/fs-writeback.c:1790 wb_writeback+0x290/0x660 fs/fs-writeback.c:1896 wb_check_background_flush fs/fs-writeback.c:1964 [inline] wb_do_writeback+0x583/0x5d0 fs/fs-writeback.c:2052 wb_workfn+0xb8/0x410 fs/fs-writeback.c:2080 process_one_work+0x3e1/0x950 kernel/workqueue.c:2272 worker_thread+0x635/0xb90 kernel/workqueue.c:2418 kthread+0x1fd/0x220 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 read to 0xffff888137c11ac0 of 4 bytes by task 28256 on cpu 1: ext4_do_update_inode fs/ext4/inode.c:5105 [inline] ext4_mark_iloc_dirty+0xcc3/0x1650 fs/ext4/inode.c:5712 __ext4_mark_inode_dirty+0x450/0x610 fs/ext4/inode.c:5906 ext4_dirty_inode+0xa6/0xc0 fs/ext4/inode.c:5942 __mark_inode_dirty+0x74/0x740 fs/fs-writeback.c:2260 mark_inode_dirty include/linux/fs.h:2183 [inline] generic_write_end+0x15e/0x250 fs/buffer.c:2202 ext4_da_write_end+0x59b/0x760 fs/ext4/inode.c:3102 generic_perform_write+0x23e/0x3a0 mm/filemap.c:3340 ext4_buffered_write_iter+0x2e5/0x3d0 fs/ext4/file.c:270 ext4_file_write_iter+0x45e/0x1090 fs/ext4/file.c:503 call_write_iter include/linux/fs.h:1903 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0x6d4/0x7c0 fs/read_write.c:605 ksys_write+0xce/0x180 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:667 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 28256 Comm: syz-executor.2 Not tainted 5.10.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================